The DYS385 genotype frequencies and gene diversity in azoospermic and fertile individuals in the Aegean Region of Turkey are shown in Table 1. A total of nine different alleles (9, 10, 11, 12, 14, 16, 17, 19, 24) were observed and allele 24 was seen only in fertile males. In azoospermic males, genotypes carrying allele 14 were the most frequent with 50.8% and allele 12 was present in 31% of fertile males. Overall, 31 different genotypes were found and 22 of these were observed in azoospermic males, while 26 were found in the fertile males. In this study, genotype 14-17 (12%) was the most common in the Aegean Region of Turkey. In azoospermic males, the frequencies were more evenly distributed with genotype 14-17 (18.3%), genotype 14-16 (12.2%) and genotype 11-14 (10.2%). Frequently seen genotypes in fertile males were 10-16, 11-12, 12-19, 14-16 and 17-19, respectively. Genotype 14-17 showed the biggest difference, with a fre­quency of 0.183 in azoospermic males and a frequency of 0.058 in fertile males. The genotype frequencies differed significantly (c2: 47.75, p <0.05) (Table 1). We can thus say that the polymorphism of DYS385 differs from azo­ospermic to fertile individuals in the Aegean Region of Turkey.

In previously published studies from other regions of Turkey, a number of different genotypes were described [16-18]. Overall, the alleles 8 to 20 and 24 were present in 64 different genotypes, 33 of which were not observed in the present study, and 10 of which were seen only in this study, but not observed in the other studies. In these previous Turkish studies, genotype 11-14 at the locus DYS385 had been the most frequent allele combination with ratios of 0.0952, 0.1416 and 0.1250, respectively.

While DYS385 had an exclusion chance of 0.917 in azoospermic males, this value was 0.949 in fertile males. For the combined subjects, this value was 0.946. This confirmed the results of the previous Turkish studies [16-18]. These results demonstrate that the DYS385 locus is very useful for human identification in forensic cases and paternity tests in the Aegean Region of Turkey.

When our results were compared with other previously published studies [9,11,12,19-30] from Asia, Europe and the USA, different results for the DYS385 locus were obtained in a population from Spain, Portugal, USA, Latvia, etc., and similar results in a population from China, Japan, USA, Italy, etc. (Table 2). From the results of the table, it can be seen that the gene diversity of the DYS385 locus was very high but varied in the different populations.

In conclusion, this is the first study about the DYS385 gene polymorphism in the Aegean Region of Turkey, and in which azoospermic and fertile males were compared for the first time. Results of the present study reveal quite a high genetic diversity of the DYS385 locus, and different genotype frequencies could be seen in many regions of Turkey. At the same time, the results demonstrate that the DYS385 locus is very useful for human identification in forensic cases and paternity tests.